JP2003287512A - Apparatus and method for monitoring concentration of oxidizing gas or oxidizing vapor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an apparatus and a method for monitoring a concentration of a oxidizing gas or oxidizing vapor by providing a real-time measured value of the concentration of the oxidizing gas (or the oxidizing vapor) inside a diffusion-restricted region. <P>SOLUTION: In a concentration monitor 410, a diffusion-restricted region 40 in fluid communication with a sterilization chamber is arranged inside a region in which a variable is generated in response to the oxidizing gas or the oxidizing vapor and in at least a part of which a diffusion is restricted. The concentration monitor comprises a first temperature sensing device 412 and a chemical substance 414 reacting with the oxidizing gas or the oxidizing vapor. The first temperature sensing device is coupled to the chemical substance so as to generate a first signal in response to heat generated by the chemical substance and the oxidizing gas or the oxidizing vapor, and the variable is generated in response to the first signal. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001] This application is a continuation-in-part application of US patent application Ser. , 594, the disclosures of which are incorporated herein by reference in their entireties.

[0002]

FIELD OF THE INVENTION The present invention relates to a method of sterilizing an article using oxidative gas or vapor, and more particularly to a concentration of oxidative gas (or oxidative vapor) during a sterilization process. Regarding how to monitor.

[0003]

BACKGROUND OF THE INVENTION Chemical sterilization involves the use of medical devices (me) during sterilization.
It has been used successfully to sterilize medical devices to minimize damage to dical devices. Chemical sterilization is used to sterilize medical instruments.
A sterilizing fluid such as hydrogen peroxide, ethylene oxide, chlorine dioxide, formaldehyde, or peracetic acid in a closed chamber is used. One commercially available form of chemical sterilization is the Ad of Irvine, California, USA, a division of Ethicon Inc.
STERRAD available from vanced Sterilization Products
There is a (registered trademark) sterilization system. The sterilization process of the STERRAD® sterilization system uses hydrogen peroxide and cold gas plasma to sterilize medical devices.

The sterilization process of the STERRAD® sterilization system is carried out as follows. The load (article) to be sterilized is placed in the sterilization chamber, the sterilization chamber is closed and the vacuum is evacuated. An aqueous solution of hydrogen peroxide is injected into the sterilization chamber and vaporized. A cold gas plasma is initiated by supplying an electric field to generate the plasma. The hydrogen peroxide vapor dissociates in the plasma and becomes a reactive species that acts on and kills the microbes. After the activated component (reactive species) reacts with the microorganism, the surface of the sterilization chamber, or between the activated components, the activated component loses high energy and recombines with oxygen. ,water,
And other non-toxic by-products are formed. When the sterilization process is complete, the plasma is stopped, the vacuum is broken, and the sterilization chamber is vented to atmospheric pressure.

In order for the sterilization process to be effective, the load (article) to be sterilized must be exposed to a sufficient concentration of hydrogen peroxide. When the equipment in the sterilization chamber reacts with hydrogen peroxide, absorbs hydrogen peroxide or condenses it, there is not enough hydrogen vapor left to vaporize the sterilization process. There is also. Therefore,
The concentration of hydrogen peroxide in the sterilization chamber is monitored to ensure that sufficient hydrogen peroxide is present. If an excess amount of hydrogen peroxide is removed from the sterilization chamber by absorption, condensation, or reaction by the instruments in the sterilization chamber, the sterilization cycle is aborted and the remaining hydrogen peroxide in the sterilization chamber is sterilized. Evacuation of the chamber and / or introduction of plasma to decompose hydrogen peroxide is removed and a new sterilization cycle is initiated.

For example, in the prior art, the concentration of hydrogen peroxide is monitored and additional hydrogen peroxide is added to bring the concentration of hydrogen peroxide to a level effective for sterilization and below the saturation limit. A method of keeping is described (for example, refer to Patent Document 1). However, the above-mentioned document (patent specification) does not describe a method for determining whether or not the device in the sterilization chamber has significantly absorbed, condensed, or decomposed a large amount of hydrogen peroxide. If hydrogen peroxide is absorbed or condensed on the instrument in the sterilization chamber, it may take a long time to remove the hydrogen peroxide so that the instrument can be safely removed from the sterilization chamber.

To monitor the effectiveness of the sterilization system,
Biological indicators have long been used. Biological indicators typically include a source of microorganisms with a predetermined concentration of dry, live microorganisms on a substrate. The substrate impregnated with microorganisms is placed in a sterilization system in which a load (article to be sterilized) is placed and undergoes treatment throughout the sterilization process. The substrate is then placed in a sterile medium and incubated at an appropriate temperature for a predetermined time with an indicator showing whether viable microorganisms are present. At the end of the culture period, the medium is tested to determine if the microorganisms survived the sterilization process. The survival of the microorganisms means that the sterilization process is incomplete. A self-contained biological indicator is a microbial source, medium packaged together so that the microbial source, medium, and indicator can be combined without exposing the biological indicator to the non-sterile surrounding environment. , And an indicator. Examples of such biological indicators are disclosed in the prior art (for example, Patent Documents 2 and 3).
reference).

In practice, the biological indicators are placed in the area of load (the article to be sterilized), above which it is concerned that the sterilization process makes it difficult to sterilize. For example, some loads include small openings or diffusion-restricted areas where hydrogen peroxide reaches and is sterilized after diffusion through long and narrow diffusion passages such as lumens. Biological indicators are made small enough to be placed in most of these diffusion restricted areas or environments. If the sterilization process kills the biological indicator microorganisms located within such diffusion-restricted area, then the sterilization process is deemed to have been performed correctly. But,
If this method is used to determine whether the sterilization process was successful, the answer (decision result) after the culture period has ended
To get

[0009]

[Patent Document 1] US Pat. No. 4,956,145 (Column 3-14, FIG. 1-4)

[Patent Document 2] US Pat. No. 5,801,010 (columns 8-9, FIG. 11)

[Patent Document 3] US Pat. No. 5,552,320 (column 4-5, FIG. 2-3)

[0010]

Since the conventional technique is configured as described above, there is a problem that the determination result of whether or not the sterilization process is successful can be obtained only after the culture period is completed. was there.

The present invention has been made to solve the above problems, and can provide a real-time measurement value of the concentration of an oxidizing gas (or oxidizing vapor) in a region where diffusion is restricted. It is an object to obtain an apparatus and method for monitoring the concentration of oxidizing gas or oxidizing vapor.

[0012]

SUMMARY OF THE INVENTION In one aspect, the present invention provides a method for monitoring the concentration of oxidizing gas (or oxidizing vapor) in a diffusion-restricted region fluidly coupled to a sterilization chamber during a sterilization process. provide. The method of monitoring its concentration involves providing a concentration monitor that produces a variable in response to an oxidizing gas (or oxidizing vapor). The concentration monitor has a first temperature detecting device and a chemical substance that reacts with an oxidizing gas (or oxidizing vapor) to generate heat. The first temperature detection device is coupled with a chemical substance and outputs a first signal in response to heat generated by the chemical substance and the oxidizing gas (or oxidizing vapor). The variable is generated in response to the first signal. The method of monitoring concentration further comprises the step of placing at least the chemical-bearing portion of the concentration monitor in the diffusion-restricted region. Method for Monitoring Concentration The method further comprises introducing oxidizing gas (or oxidizing vapor) into the sterilization chamber. The method of monitoring concentration is the process of monitoring the variables generated by the concentration monitor during the sterilization process to monitor the concentration of oxidizing gas (or oxidizing vapor) in the diffusion-limited region during the sterilization process. Further has.

In another aspect, the invention provides an apparatus for monitoring the concentration of oxidizing gas (or oxidizing vapor) in a sterilization chamber during a sterilization process. The concentration monitoring device has a diffusion limited region fluidly coupled to the sterilization chamber. The concentration monitoring device further comprises a concentration monitor that produces a variable in response to the oxidizing gas (or oxidizing vapor). At least a portion of the concentration monitor is within the diffusion limited region. The concentration monitor has a first temperature detecting device and a chemical substance that reacts with an oxidizing gas (or oxidizing vapor) to generate heat. The first temperature detection device is coupled with a chemical substance and outputs a first signal in response to heat generated by the chemical substance and the oxidizing gas (or oxidizing vapor). The variable is generated in response to the first signal.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIGS. 1, 2, 3, 4, and 5 are diagrams showing an embodiment of a concentration monitor 10 that is compatible with an embodiment of the present invention. In one embodiment of the invention, concentration monitor 10 includes carrier 12
, A chemical substance 14, and a temperature probe 16. All of the components that make up the concentration monitor 10 must be compatible with the operating conditions of the concentration monitor 10. The concentration monitor 10 compatible with the present invention can operate under a wide range of pressures, such as atmospheric pressure or sub-atmospheric pressure (ie, partial vacuum). Carrier 12, chemistry 14, and temperature probe 16 are all compatible for sterile operation and exposure to hydrogen peroxide and plasma for use in hydrogen peroxide sterilization systems with and without plasma Must. One of ordinary skill in the art will appreciate that a variety of materials and configurations can be selected for the carrier 12 in these embodiments.
The carrier 12 tightly bonds the chemical substance 14 to the temperature probe 16 so that the heat loss between the chemical substance 14 and the temperature probe 16 is minimized. Suitable materials for carrier 12 include, but are not limited to, acrylic resin, epoxy resin, nylon, polyurethane, polyhydroxyethyl methacrylate.
enemethacrylate: polyHEMA), polymethylmethacrylate (PMMA),
Polyvinylpyrrolidone (PV)
P), polyvinyl alcohol (polyvinyalcohol: PV
A), silicone, tape, vacuum grease. Further, the carrier 12 is configured to expose the chemicals 14 directly to the ambient environment, but still comprises a gas permeable pouch or one or more openings, such as a Tyvek (R) tube. It may also be configured to be surrounded by a gas impermeable enclosure.
In one embodiment, the chemistry 14 may be bound directly to the temperature probe 16 without a carrier. For example, the chemistry 14 is formed as an integral part of the temperature probe 16, and the chemistry 14 is directly bonded to the temperature probe 16 if the chemistry 14 is sufficiently adhesive.
Chemical vapor deposition or electroplating may be used to bond the chemistry 14 directly to the temperature probe 16.

When exposed to a monitored oxidizing gas (or oxidizing vapor), the chemical substance 14 produces a detectable amount of thermal energy (ie, heat) while producing a monitored oxidizing gas (or oxidizing vapor). It causes a thermal reaction with (oxidizing vapor).
One of ordinary skill in the art can select a suitable chemical 14 that will obtain a sufficient amount of heat when exposed to a monitored range of concentrations of oxidizing gas (or oxidizing vapor). Examples of chemicals 14 used in a hydrogen peroxide sterilization system include, but are not limited to, substances that catalytically decompose hydrogen peroxide, substances that are easily oxidized by hydrogen peroxide, and hydroxyl functional groups. There are substances that contain groups. Substances that decompose hydrogen peroxide by catalysis include, but are not limited to, catalase, copper and copper alloys,
There are iron, silver, platinum and palladium. Substances that are easily oxidized by hydrogen peroxide include, but are not limited to, magnesium chloride (MgCl ₂ ), iron acetate (I
I) and other iron (II) compounds, potassium iodide (K
I), sodium thiosulfate, and sulfides and disulfides such as molybdenum disulfide, 1,2-ethanedithiol, methyl disulfide, cysteine, methionine, polysulfides. Substances containing hydroxyl functional groups include
Non-limiting examples include polyethylene glycol (PEG), polyethylene oxide (PEO), polyvinyl alcohol (PVA). These substances are
It may be in the form of a polymer having hydroxyl functional groups and those skilled in the art will appreciate that such a polymer may be a copolymer. Further, a combination of the above-mentioned substances may be selected as the chemical substance 14. Further, one of ordinary skill in the art can select an appropriate amount of chemical substance 14 to obtain a sufficient amount of heat when exposed to a range of concentrations of hydrogen peroxide.

Various configurations suitable for use in the embodiments of the present invention are shown in FIGS. 1, 2, 3, 4, and 5.
Is illustrated in. FIG. 1 shows a temperature probe 16 whose tip is covered with a carrier 12 composed of a thin layer, and a chemical substance 14 is formed so as to cover the outside of the carrier 12. FIG. 2 shows a temperature probe 1 mixed with a carrier 12.
6 is a diagram showing the chemical substance 14 applied to the tip of FIG. For example, a chemical substance 14 such as PEG is mixed with a carrier 12 such as an acrylic binder in an aqueous suspension and then applied to a temperature probe 16. Chemicals 14 are accessible for reaction as hydrogen peroxide diffuses into the carrier 12. FIG. 3 is a view showing the chemical substance 14 surrounded by the tip of the temperature probe 16 by the carrier 12. The carrier 12 is a gas permeable pouch with a heat seal portion 17, typically an EI du Pont d, Wilmington, Del.
CSR consisting of Tyvek® made of non-woven polyethylene sold by eNemours and Co. or non-woven polypropylene sold by Kimberly-Clark Corp. of Dallas, Texas, USA.
(Central supply room) Made from non-woven polypropylene material such as wrapping material. Carrier 12
Is a gas impermeable pouch or other enclosure with one or more openings that allows the gas or vapor to diffuse and react with the chemicals 14 retained within the enclosure. May be. FIG. 4 shows that the carrier 12 is made of a heat conductive material 18
The thermally conductive material 18 is bound to the temperature probe 16 by the substrate 19, showing the chemical substance 14 bound to the. The substrate 19 may be tape, adhesive, or other bonding means. The thermally conductive material 18 may be a metal wire or other material that can properly conduct heat to the temperature probe 16. FIG. 5 shows the chemical substance 14 bound to the temperature probe 16 by the carrier 12, the two parts of the temperature probe 16 being joined and separated from each other by the male connector 20 and the female connector 21.

The temperature probe 16 is a device for measuring the temperature at a specific position. In one embodiment of the present invention, the temperature probe 16 is a Luxtron® 3100.
A fiberoptic temperature probe, such as a fluoroptic thermometer.
re probe). This optical fiber temperature probe 1
Since 6 is coated with Teflon (registered trademark), it has high compatibility with any oxidizing gas (or oxidizing vapor). In another embodiment, the temperature probe 1 comprises a thermocouple probe 16 using a bond of two metals or alloys.
6 is used. Thermocouple junctions generate a voltage that is a known function of junction temperature. Therefore, the measured voltage across the thermocouple junction is converted to a measured temperature at the junction. Thermocouple joints can be made very small (eg diameters of 0.025 mm made of different alloys).
The two wires are made by spot welding) and can be placed in a volume constrained volume. In yet another embodiment, the temperature probe 16 includes a thermistor, a glass thermometer, a resistance temperature detector (RT).
D) Probe, temperature strip
p), optical temperature sensor,
Alternatively, it is composed of an infrared temperature sensor.

Table 1 shows the increase in temperature measured by the concentration monitor 10 using potassium iodide (KI) as the chemical substance 14. The tip of the fiber optic temperature probe is first coated with a thin layer of Dow Corning high vacuum grease (part number 2021846-0888). Next, substantially 0.15 g of potassium iodide (KI) powder is applied to the high vacuum grease. This configuration is equivalent to that shown in FIG. For the measurement, the concentration monitor 10 was suspended in a vacuum chamber heated to 45 ° C., the vacuum chamber was evacuated, the initial temperature of the temperature probe was measured, hydrogen peroxide was injected into the vacuum chamber, and all This was done by measuring the temperature after the hydrogen peroxide was vaporized and ventilating the vacuum chamber. The measurement was repeated with varying concentrations of hydrogen peroxide injected. The same temperature probe 16 was used for all measurements and the results shown in Table 1 were obtained. As can be seen from Table 1, potassium iodide (KI) produced a measurable increase in temperature with increasing concentration of hydrogen peroxide. The concentration monitor 10 can be reused many times.

[Table 1]

Table 2 shows data relating to the measured increase in temperature for changes in the concentration of hydrogen peroxide on the same concentration monitor 10 when different chemicals 14 were used. The same test conditions and probe configurations were used for these measurements. As can be seen from Table 2, each of the chemicals 14 produced an increase in temperature with increasing concentration of hydrogen peroxide.

[Table 2]

The utility of using a thermocouple junction as the temperature probe 16 is shown in Table 3. For the measurements shown in Table 3, the concentration monitor 10 was constructed as shown in FIG. The same test conditions as in Table 1 were used for the measurements in Table 3. Table 3 shows that a significant increase in temperature was also observed using the thermocouple temperature monitor 16.

[Table 3]

The utility of using double sided tape as the carrier 12 is shown in Table 4, which shows the increase in temperature measured by the temperature probe 16 of the optical fiber. First, a thin layer of 3M Scotch double-sided tape was applied to the tip of the temperature probe 16 of the optical fiber. Substantially 0.15 g of potassium iodide (KI) powder was then applied to the double-sided tape. The same test conditions as in Table 1 were used for the measurements in Table 4. From Table 4, when the double-sided tape is used as the carrier 12, H ₂
It can be seen that a significant increase in temperature was detected with an increase in the concentration of O ₂ (hydrogen peroxide).

[Table 4]

The utility of using an epoxy resin as the carrier 12 is shown in Table 5, which shows the increase in temperature measured by the temperature probe 16 of the optical fiber. Concentration monitor 10 is Cole-Palmer877
8 Made by applying epoxy resin to aluminum wire.
Then, substantially 0.15 g of potassium iodide (KI) powder was applied to the epoxy resin and dried. Finally, an aluminum wire was attached to the temperature probe 16. The same test conditions as in Table 1 were used for the measurements in Table 5. It can be seen that when an epoxy resin is used as the carrier 12, a significant increase in temperature is detected with an increase in the concentration of H ₂ O ₂ (hydrogen peroxide).

[Table 5]

A carrier 1 to surround the chemical substance 14.
Table 6 shows the usefulness of using enclosures as
And shown in Table 7, which shows the increase in temperature detected by the optical fiber temperature probe 16 with potassium iodide (KI) housed in the enclosure. There is. In Table 6, the enclosure consists of PVC shrink tubing with openings. The openings are sized to allow the containment of potassium iodide (KI) powder and to allow the gas (or vapor) to diffuse into the PVC shrink tube. Table 7
In, the enclosure is a gas-permeable T made from heat-sealed 1073B Tyvek®.
It consists of yvek® tubes. The inner diameter of the enclosure is substantially 0.5 cm and the length of the enclosure is substantially 1.5 cm. In Table 6, substantially 0.2 g of potassium iodide (KI) powder was contained in a PVC shrink tube and the same concentration monitor 10 was used for all measurements. In Table 7, substantially 0.2 g of potassium iodide (KI) powder was contained in a Tyvek® pouch and the same concentration monitor 10 was used for all measurements. The same test conditions as in Table 1 were used for the measurement. In either case of using the two embodiments of gas permeable pouch as carrier 12, H ₂ O ₂ (hydrogen peroxide)
It can be seen that a significant increase in temperature was detected with an increase in the concentration of. The results shown in Table 6 and Table 7 are
It also shows that the concentration monitor 10 can be used repeatedly and the measured values are reproducible.

[Table 6]

[Table 7]

Chemicals 14 having polymers with hydroxyl functional groups can also be used to make hydrogen peroxide monitors. For example, polyethylene glycol (PEG) in the formulation of H (OCH ₂ CH ₂ ) _n OH mixed with an acrylic binder in an aqueous suspension provides a hydrogen peroxide monitor compatible with the present invention. Such chemicals have a high specificity for oxidizing gases (or oxidizing vapors) such as hydrogen peroxide (H ₂ O ₂ ), and have essentially no sensitivity to H ₂ O. It will be apparent to those skilled in the art that other polymers having hydroxyl functionality are also compatible with the present invention.

To test the usefulness of PEG and acrylic (binder) suspensions, various hydrogen peroxide (H ₂ O)
₂ ) A monitor was manufactured using the following procedure. A mixture of PEG and acrylic (binder) in a weight ratio of 1 to 1 gives 5 g of acrylic binder (Vivitone, Inc. product number 37-14125-001 metal binder LNG).
PEG (Aldrich, Inc. product number 30902-8,
The molecular weight was substantially 10,000) and mixed and stirred in a 20 g scintillation vial. In other embodiments compatible with the present invention, ratios other than 1: 1 may be used. The mixture was then heated to substantially 75 ° C and stirred well. After the mixture was cooled to room temperature, the vial containing the suspension was capped and stored in a cool dark environment.

To produce each hydrogen peroxide (H ₂ O ₂ ) monitor, the metal surface of the thermocouple was chemically treated to facilitate attachment of the chemical substance 14 to the carrier 12. The thermocouple was immersed in isopropyl alcohol for substantially 2 minutes and the ends of the thermocouple were lightly brushed to remove debris. After air drying for substantially 5 minutes, the thermocouple ends have a volume percentage of substantially 10% to 20% for substantially 2 minutes.
% Sulfuric acid (H ₂ SO ₄ ), then rinsed thoroughly in water with abundant ion removal. The thermocouple was then dried in the oven at substantially 55 ° C. for substantially 5 minutes and then cooled outside the oven to room temperature for substantially 5 minutes. The end of the thermocouple was then coated with a mixture of PEG and acrylic (binder) by dipping the end of the thermocouple into a vial containing the mixture.
To thicken the entire coating, the thermocouple ends can be repeatedly dipped. The thermocouple was then returned to the oven and dried at a temperature of substantially 55 ° C. for substantially 5 minutes.
A similar procedure was used to make a PEO and acrylic (binder) hydrogen peroxide (H ₂ O ₂ ) monitor.

The procedure described above is durable, inexpensive and
An easily manufactured hydrogen peroxide (H ₂ O ₂ ) monitor can be created. In addition, PEG and acrylic (binder)
The mixture has a relatively long shelf life of substantially 3 years or more. By using a coating of a suspension of PEG and acrylic (binder), very small and flexible hydrogen peroxide (H ₂ O ₂ ) monitors of various sizes and shapes can be manufactured. For example, if you want to measure the concentration of hydrogen peroxide (H ₂ O ₂ ) in a narrow tube, the reactive chemical is Luxtron.
(Registered trademark) fluoroptic thermom
eter), a fiber optic temperature probe, or a thermistor or thermocouple assembly coated over a metal wire.

PEG and acrylic prepared by the above-mentioned procedure
Hydrogen peroxide (binder)₂O ₂) Monitor and
Hydrogen peroxide (H) of PEO and acrylic (binder)₂O₂)
Monitor shows low temperature peroxide of STERRAD (registered trademark) 100
It was tested in a hydrogen gas plasma sterilization system. these
Hydrogen peroxide (H₂O₂) Monitor hydrogen peroxide vapor
Table 8 shows the sensitivity to
Different concentrations of hydrogen peroxide (H
₂O₂) To hydrogen peroxide (H₂O₂) The monitor appears
The measured increase in applied temperature (° C.) is shown. Warm
The change in temperature (increase in temperature) is due to hydrogen peroxide (H₂O₂)
Measured temperature with a thermocouple before injection
Is a value based on.

[Table 8]

[0029] The measured value of the temperature increase in the relative concentration of a known hydrogen peroxide (H ₂ O _2), the hydrogen peroxide (H ₂ O
₂ ) Can be used to create a calibration curve for the monitor. The response of each hydrogen peroxide (H ₂ O ₂ ) monitor to hydrogen peroxide (H ₂ O ₂ ) using the same chemical and carrier (binder) mixture is substantially equal to each other,
This indicates that hydrogen peroxide (H ₂ O ₂₎ with hydrogen peroxide (H ₂ O ₂₎ monitor reproducibility for response is achieved. Same chemical substance and carrier (binder)
There is sufficient reproducibility between hydrogen peroxide (H ₂ O ₂ ) monitors using a mixture of so that the standard reaction equation describes the response of all those hydrogen peroxide (H ₂ O ₂ ) monitors. Therefore, no calibration per hydrogen peroxide (H ₂ O ₂ ) monitor is required to translate temperature changes into measurements of hydrogen peroxide (H ₂ O ₂ ) concentration.

A hydrogen peroxide (H ₂ O ₂ ) monitor compatible with the present invention using a reactive chemical and carrier such as a mixture of PEG and acrylic (binder) is a temperature probe other than a thermocouple. Can also be used. Suitable temperature probes 16 include, but are not limited to,
Glass thermometer, thermocouple, thermistor, RTD probe,
There are temperature strips, light temperature sensors, and infrared temperature sensors. Further, the sensing surface of the temperature probe 16 may be chemically or mechanically etched to improve the adhesion between the reactive chemistry 14 and the temperature probe 16. The reactive chemistry 14 may be exposed to temperature by various methods such as, but not limited to, dipping, painting, spraying, chemical vapor deposition, electrochemical plating. It may be applied to cover the temperature sensing surface of probe 16. In order to shorten the response time, the chemical substance 1 should be added to the temperature probe 16.
It is preferable to form a thin coating of 4 to reduce the thermal mass. The thickness of the coating depends on the temperature probe 16
It is controlled by adjusting the residence time when the coating is formed or the rate at which the temperature probe 16 is withdrawn from the solution (of the mixture), and by adjusting the viscosity of the reactive chemical 14. In addition to the initial coating, additional coatings of reactive chemicals may be formed to improve either or both signal strength and sensitivity.

FIG. 6 is a diagram schematically showing a sterilization system 25 using an embodiment of the present invention. The sterilization system 25 has a vacuum chamber 30 with a door 32, through which the articles to be sterilized are vacuum chamber 3
0 and removed from the vacuum chamber 30.
The door 32 is operated using the door controller 34. The vacuum chamber 30 further has a door controller 34, a gas inlet system 40, a gas outlet system 50, and a radio frequency system (rf system) 60. Another embodiment compatible with the present invention is US Patent Application Serial No. 09 / 676,919 entitled "Sterilization System".
A low frequency plasma sterilization system as described in "Employing Low Frequency Plasma" can be used. The gas inlet system 40 uses hydrogen peroxide (H
₂ O ₂ ) supply source 42, valve 44, and valve controller 46
Have and. The gas outlet system 50 has a vacuum pump system 52, a valve 54, a valve controller 56, and a vacuum pump system controller 58. To provide radio frequency energy to hydrogen peroxide (H ₂ O ₂ ) in the vacuum chamber 30, the rf system 60 includes a ground electrode 62, a powered electrode 64, and a power source 66.
And a power controller 68. Sterilization system 2
5 is operated using a control system 70, which receives input from the operator and which controls the door controller 34, the valve controller 46, the valve controller 56,
Signals to vacuum pump system controller 58 and power controller 68. A concentration monitor 10 is connected to the control system 70 (for example, a microprocessor), and the concentration monitor 10 sends a signal to the control system 70, and the signal is generated in the vacuum chamber 30 at a position where the concentration monitor 10 is located. Converted to information about hydrogen oxide (H ₂ O ₂ ). The article 80 to be sterilized is placed in the vacuum chamber 30 with the concentration monitor 10 placed in the load area (the area where the article 80 to be sterilized is placed) to monitor the concentration of hydrogen peroxide in the load area. And is shown in the figure. One of ordinary skill in the art can select an appropriate device for properly carrying out the present invention.

Oxidizing gas (or oxidizing vapor) and chemical substance 1
The heat produced by 4 may not be the same as the composition of concentration monitor 10, carrier 12, and chemistry 14 changes. Therefore, the concentration monitor 10
For each type of, a calibration curve needs to be established to determine the relationship between the concentration of oxidizing gas (or oxidizing vapor) and the heat produced. Once the calibration curve is established, the heat detected during the measurement can be converted to the concentration of oxidizing gas (or oxidizing vapor) around the concentration monitor 10.

The operation of the sterilization system 25 is monitored by the concentration monitor 1
By combining with the concentration of hydrogen peroxide (H ₂ O ₂ ) measured by 0, the sterilization system 25 produces a suitable amount of hydrogen peroxide (H ₂ O ₂ ) in the area where the article to be sterilized is located.
₂ O ₂ ) is ensured. First, if the hydrogen peroxide (H ₂ O ₂ ) concentration is determined to be too low for proper sterilization, the control system 70 opens the inlet valve 44 to the inlet valve controller 46. To send more hydrogen peroxide (H ₂ O ₂ ) into the vacuum chamber 30. Alternatively, if the hydrogen peroxide (H ₂ O ₂ ) concentration is determined to be too high, the control system 70 causes the outlet valve controller 56 to exit.
May be signaled to open the outlet valve 54 to allow the vacuum pump system 52 to remove some hydrogen peroxide (H ₂ O ₂ ) from the vacuum chamber 30. Moreover, sterilization system 25 is operating in a dynamic mode (i.e., hydrogen peroxide (H ₂ O ₂₎ at the same time hydrogen peroxide while being introduced into the vacuum chamber 30 from the inlet of the valve 44 (H ₂
O ₂ ) is being evacuated from the vacuum chamber 30 via the outlet valve 54), either or both of the inlet valve 44 and the outlet valve 54 are measured hydrogen peroxide (H ₂ O is adjusted in accordance with the concentration of ₂₎ may be to maintain an appropriate level of hydrogen peroxide (H ₂ O _2).

The concentration monitor 10 uses hydrogen peroxide (H
₂ O ₂ ) to provide local information on the concentration of
Sterilization chamber (vacuum chamber) 30 for concentration monitor 10
Precise placement within is important. In one embodiment, the concentration monitor 10 is fixed in a particular location within the sterilization chamber (vacuum chamber) 30 near the article 80 to be sterilized. In other embodiments, the concentration monitor 10 is not fixed to a particular location within the sterilization chamber (vacuum chamber) 30 but is placed directly on or near the article 80 to be sterilized. It In this way, the concentration monitor 10 is used to measure the concentration of hydrogen peroxide (H ₂ O ₂ ) to which the article 80 to be sterilized is exposed. In particular, the item 80 to be sterilized is
If there is a portion that is exposed to low concentrations of hydrogen peroxide (H ₂ O ₂ ) such as by a small opening (usion) or a narrow opening, the concentration monitor 10 will be placed in that portion and will have a sufficient concentration of excess to sterilize the portion. It is possible to ensure that hydrogen oxide (H ₂ O ₂ ) is retained. The small size of the concentration monitor 10 of the present invention allows the concentration monitor 10 to be placed in a volume inside a lumen or in a very narrow volume, such as in a container or encased tray. In yet another embodiment of the present invention, multiple concentration monitors 10 are used to measure the concentration of hydrogen peroxide (H ₂ O ₂ ) at various locations of interest.

The temperature of the temperature probe 16 in the sterilization chamber (vacuum chamber) 30 may fluctuate due to other factors unrelated to the concentration of hydrogen peroxide. Such temperature fluctuations that are not related to the concentration of hydrogen peroxide cause hydrogen peroxide (H) in the sterilization chamber (vacuum chamber) 30.
₂ O ₂ ) may be erroneously recognized as being due to a change in concentration, resulting in a measurement error. In one embodiment, as shown in FIG. 7, the reference temperature probe 90 along with the temperature probe 16 of the concentration monitor 10 is used.
Is used to measure the ambient temperature in the sterilization chamber (vacuum chamber) 30 to enhance the performance of the concentration monitor 10.

A reference temperature probe 90 located near the temperature probe 16 is used to measure temperature fluctuations independent of the concentration of hydrogen peroxide (H ₂ O ₂ ) and is used to measure the temperature of the temperature probe 16. From these measurements compensates for temperature fluctuations independent of the concentration of these hydrogen peroxides (H ₂ O ₂ ). In one embodiment, temperature fluctuations independent of the concentration of hydrogen peroxide (H ₂ O ₂ ) are monitored at substantially the same time as the temperature probe 16 temperature reading (measurement). Typically, the reference temperature probe 90 is substantially the same as the temperature probe 16 except that it has no reactive chemistry 14. For example, a hydrogen peroxide (H ₂ O ₂ ) concentration monitor 10 for a mixture of PEG and acrylic (binder) may include a reference temperature probe 90 with an acrylic binder and no PEG polymer. Instead, hydrogen peroxide (H ₂ O
₂ ) Concentration monitor 10 is a chemical substance that is also reactive with the binder.
A bare reference temperature probe 90, which does not have the above, may be provided.

In the embodiment schematically illustrated in FIG. 7, the concentration monitor 10 includes a reference temperature probe 90 and a temperature probe 16, and the reference temperature probe 90 is separated from the temperature probe 16. In such an embodiment,
The concentration monitor 10 includes a microprocessor 100,
The temperature probe 16 is separately connected to the data acquisition channel 102 of the microprocessor 100, and the reference temperature probe 90 is separately connected to the data acquisition channel 104 of the microprocessor 100. Microprocessor 100
Includes an algorithm in hardware and / or software, which subtracts the ambient temperature determined by the reference temperature probe 90 from the temperature detected by the temperature probe 16 to produce a sterilization chamber (vacuum chamber). The increase in temperature due to the concentration of the oxidizing gas (or oxidizing vapor) in 30 is obtained.
In such an embodiment, the electrical connection between the temperature probe 16 and the reference temperature probe 90 and the microprocessor 100 requires two data acquisition channels, which may be one implementation. In the form of the temperature probe 16 and the reference temperature probe 90.
Too large to allow placement in a narrow lumen.

In one embodiment, as illustrated schematically in FIG. 8, the concentration monitor 10 includes a first thermocouple junction 110 and a chemical substance bonded to the first thermocouple junction 110. 14 and. The chemical substance 14 reacts with an oxidizing gas (or oxidizing vapor) to generate heat. The first thermocouple junction 110 includes a first conductor 112 and a first conductor 112.
And a second conductor 114 connected to
Reference numeral 14 is a conductor of a type different from that of the first conductor 112.

The concentration monitor 10 further comprises a second thermocouple junction 120, which in one embodiment is substantially the same as the first thermocouple junction 110. Second thermocouple junction 1
20 is connected in series with the first thermocouple junction 110. In one embodiment, the second thermocouple junction 120 includes a third conductor 11 as shown schematically in FIG.
6 and the second conductor 114, the third conductor 116 is connected to the second conductor 114. In embodiments where the second thermocouple junction 120 is substantially equal to the first thermocouple junction 110, the third conductor 116 is substantially equal to the first conductor 112. For example, the first conductor 112 and the third
The conductor 116 is made of a constantan (copper nickel alloy) wire, and the second conductor 114 is made of an iron wire. Therefore, the two J type thermocouple junctions are connected in series. Typically, such thermocouple junctions have a sensitivity on the order of μV / ° C. The first thermocouple junction 110 and the second thermocouple junction 120 are qualitatively thermally insulated from each other and are arranged in the same diffusion restricted region.

In this specification, "region where diffusion is restricted"
The term refers to a region where the oxidizing gas (or oxidizing vapor) reaches only after being diffused through a diffusion limiting structure such as a small opening, a gas permeable diaphragm, or a long and narrow diffusion passage such as a lumen.

When placed in an environment free of oxidizing gas (or oxidizing vapor), first thermocouple junction 110 and second thermocouple junction 120 each generate a voltage indicative of ambient temperature. In an embodiment in which the second thermocouple junction 120 is substantially equal to the first thermocouple junction 110, the first thermocouple junction 110 and the second thermocouple junction 120 have equal values and polarities. Generates the opposite voltage, the first
Thermocouple junction 110 and second thermocouple junction 120
The total voltage across both is zero. Therefore, the concentration monitor 10 keeps the overall voltage across both the first thermocouple junction 110 and the second thermocouple junction 120 at zero in an environment where there is no oxidizing gas (or oxidizing vapor),
Responds to temperature fluctuations.

When the chemical substance 14 is exposed to an oxidizing gas (or oxidizing vapor), the heat generated by the chemical substance 14 raises the temperature of the first thermocouple junction 110, while the second thermocouple junction 120. The temperature of remains essentially unchanged with ambient temperature. In an embodiment in which the second thermocouple junction 120 is substantially equal to the first thermocouple junction 110, the voltage generated by the first thermocouple junction 110 is in the presence of oxidizing gas (or oxidizing vapor). When it does, it is different from the voltage generated by the second thermocouple junction 120. First thermocouple junction 1
The overall voltage across both 10 and the second thermocouple junction 120 is the first thermocouple junction 1 with chemistry 14.
Second thermocouple junction 12 without 10 and chemical substance 14
Corresponds to a temperature difference from 0. Oxidizing gas (or oxidizing vapor)
Any temperature fluctuations that are not due to the concentration of H.sub.2 will equally affect both the first thermocouple junction 110 and the second thermocouple junction 120, and thus the first thermocouple junction 110.
And the overall voltage across both the second thermocouple junction 120 is responsive to the concentration of oxidizing gas (or oxidizing vapor).

In one embodiment, first thermocouple junction 110 and second thermocouple junction 120 are each formed by welding two conductors of different materials. Alternatively, one or both of the first thermocouple junction 110 and the second thermocouple junction 120 may be formed by twisting two conductors made of different materials. In other embodiments compatible with the present invention, first thermocouple junction 110 and second thermocouple junction 120 are formed by connecting two conductors using other methods. As schematically shown in FIGS. 7 and 8, the conductor of one embodiment comprises a metal wire. First
Thermocouple junction 110 and second thermocouple junction 120
The materials of the conductors that make up the are selected to provide sufficient thermoelectric sensitivity, generally low cost, high electrical conductivity, low thermal conductivity, and good material compatibility for the sterilization process at the thermocouple junction. It

As illustrated schematically in FIG. 9, in one embodiment, the concentration monitor 10 has a linear shape and includes a first thermocouple junction 110 and a second thermocouple junction 120. Have. The first thermocouple junction 110 has a first
The first conductor 112 and the second conductor 114 are formed so that the first conductor 112 and the second conductor 114 are arranged substantially on the same straight line. The second thermocouple junction 120 includes the second conductor 11 so that the second conductor 114 and the third conductor 116 are arranged substantially on the same straight line.
It is formed by combining the fourth conductor 116 and the third conductor 116. First
The thermocouple junction 110 is bonded to the chemical substance 14, and the second thermocouple junction 120 is not bonded to the chemical substance 14. This embodiment is particularly useful for monitoring the concentration of oxidizing gas (or oxidizing vapor) within a long and narrow lumen. Similarly, in the embodiment schematically illustrated in FIG. 10, the concentration monitor 10 has a T shape. Other shapes are also compatible with embodiments of the present invention, and the particular embodiments utilized may be designed to fit the region where the concentration of oxidizing gas (or oxidizing vapor) is measured.

As schematically illustrated in FIG.
In one embodiment, the concentration monitor 10 includes a first connector 130, a second connector 132, and a cable 13.
4, a data acquisition channel 136, and a microprocessor 138. First connector 130 and second
Connectors 132 of are coupled together to electrically connect first conductor 112 and third conductor 116 to data acquisition channel 136 of microprocessor 138 via cable 134. The first connector 130 and the second connector 132 can also be decoupled from each other, for example so that the concentration monitor 10 can be placed in different positions within the sterilization chamber (vacuum chamber 30).

The embodiment schematically illustrated in FIGS. 8-11 provides advantages over the embodiment schematically illustrated in FIG. First, unlike the two data acquisition channels shown in FIG. 7, two thermocouple junctions connected in series (first thermocouple junction 110 and second thermocouple junction 120) are oxidized. Only one detection circuit (or one data acquisition channel) is required to monitor the gas (or oxidizing vapor) concentration. Not only is there a potential cost savings, but the use of only one detection circuit (or one data acquisition channel) allows the potential impact of variations in multiple detection circuits (or multiple data acquisition channels). It can be lost. Second
And the overall voltage across the two thermocouple junctions (first thermocouple junction 110 and second thermocouple junction 120) is
Since it represents the temperature difference rather than the absolute value of the temperature, the dynamic range (variation range) of the voltage value becomes smaller, and when an analog / digital converter with a specified number of bits is used in a chemical concentration measurement system. Will provide greater accuracy. Third, only one pair of conductors (two conductors) is needed to detect the overall voltage across the two thermocouple junctions (first thermocouple junction 110 and second thermocouple junction 120). Therefore, the concentration monitor 1
The size of 0 can be smaller to fit in various diffusion-constrained environments such as narrow lumens.

As schematically illustrated in FIG. 12A, in one embodiment, the concentration monitor 10 comprises an integrated circuit chip 140, the integrated circuit chip 140 having a first thermocouple junction 110. , The second thermocouple junction 120,
The chemistry 14, a circuit containing a microprocessor (or other detection circuit (not shown)). Integrated circuit chip 140 is configured to output a signal from one or more output pins 142 for transmitting the measured concentration value to other portions of the chemical concentration measurement system. In one embodiment, standard lithographic techniques (lithogra
The first thermocouple junction 110 and the second thermocouple junction 120 are produced by depositing and etching overlapping metal layers of different materials on the substrate using phic techniques. Those skilled in the art can manufacture such a concentration monitor 10 according to the present invention.

In one embodiment, as illustrated schematically in FIG. 12B, the first thermocouple junction 110.
And the second joint 120 includes a first conductor 112 and a second conductor
Of the conductor 114 and the third conductor 116 of
One or more of the first conductor 112, the second conductor 114, and the third conductor 116 have a conductive thin film structure. The chemistry 14 is bonded to the first thermocouple junction 110, and in some embodiments, the chemistry 14 also has a thin film structure. In an embodiment in which the first thermocouple junction 110 and the second thermocouple junction 120 formed by the thin film conductors are part of a thin film concentration monitor 150, the signal representative of the measured concentration is It is output from one or a plurality of output pins 152.
In one embodiment, the thin film concentration monitor 150 may be incorporated within the package of the item to be sterilized, which provides local concentration information from multiple items to be sterilized.

Embodiments in which the first thermocouple junction 110 is substantially equal to the second thermocouple junction 120 provide additional advantages. First, due to ambient temperature,
Since the overall voltage across the two thermocouple junctions (first thermocouple junction 110 and second thermocouple junction 120) is zero, no algorithm for ambient temperature correction is needed. Second, it does not require cold junction temperature compensation, as ambient temperature does not contribute substantially. Third, only a very small amount of second conductor 114 is required to form the two thermocouple junctions (first thermocouple junction 110 and second thermocouple junction 120). Therefore, the cost can be reduced as compared with the other embodiments.

FIG. 13 is a diagram schematically showing a sterilization system 210 disclosed in the prior art. Examples of such sterilization systems are Van Den Berg et al., US Pat. No. 5,847,393, Stewart et al., US Pat. No. 5,872,359, Goldenberg et al., US Pat. , 141, and Prieve
U.S. Pat. No. 6,269,680. Other sterilization systems 210 are also compatible with embodiments of the present invention, and the sterilization system 210 schematically illustrated in FIG. 13 is not intended to limit the present invention.

The sterilization system 210 includes a sterilization chamber 22.
0, hydrogen peroxide supply source 230, and concentration monitor 240
And a vacuum system 250 with a valve 252, a pump 254, and a vent 256. Sterilization chamber 22
0 is sufficiently airtight to accommodate the load (article) 260 to be sterilized and to maintain a vacuum of substantially 300 mT or less. The sterilization system 210 also has a process controller (not shown), which processes user instructions, system status, and concentration monitor 240.
A control signal is transmitted to the hydrogen peroxide supply source 230 and the vacuum system 250 according to the concentration of hydrogen peroxide determined by The sterilization system 210 also has a plasma generation system (not shown).

The concentration monitor 240 is the sterilization chamber 22.
The concentration of hydrogen peroxide vapor in zero can be measured. Among the conventional methods for measuring the concentration of hydrogen peroxide vapor are pressure measurement, dew point measurement, near-infrared absorption measurement, and ultraviolet measurement. For example, as schematically shown in FIG. 13, the density monitor 240 includes an ultraviolet light source 242.
(Eg, a mercury lamp), and an ultraviolet spectrometer 244. The ultraviolet light emitted from the ultraviolet light source 242 is transmitted to the ultraviolet spectrometer 244 through a vacuum. The vapor of hydrogen peroxide in the sterilization chamber 220 absorbs ultraviolet light of a particular wavelength and the amount of ultraviolet light absorbed is a function of the hydrogen peroxide concentration.

With such a configuration, the density monitor 240
Provides information regarding the average concentration of hydrogen peroxide in the sterilization chamber 220. However, for loads (articles) 260 with diffusion-constrained areas (eg, small crevices, and long narrow lumens), the concentration monitor 240
The measured value of the concentration by does not necessarily correspond to the concentration of hydrogen peroxide in such a diffusion limited region. Besides the general problem that the diffusion of hydrogen peroxide is restricted by such a restricted passage, the method using an aqueous solution of hydrogen peroxide has some disadvantages. First, because water has a higher vapor pressure than hydrogen peroxide, water vaporizes from the aqueous solution faster than hydrogen peroxide. Second, because water has a lower molecular weight than hydrogen peroxide, water diffuses faster in the gas phase than hydrogen peroxide. Therefore, when the aqueous solution of hydrogen peroxide vaporizes in the region around the load 260, the water vapor initially reaches the load 260 at a higher concentration. Therefore, with water vapor,
Entry of hydrogen peroxide vapor into the diffusion-restricted area is prevented or reduced.

In an attempt to determine the concentration of hydrogen peroxide in the diffusion limited region of load 260, test pack 270 is typically introduced into sterilization chamber 220 in which load 260 is located. FIG. 14 is a diagram schematically showing an example of the test pack 270 disclosed in the related art. Smith US Patent No. 5,55
Test pack 270 includes an outer opening 272, an elliptical annular passage 27, as described in US Pat.
3 and a biological indicator 271 in fluid connection with the surrounding atmosphere via an inner opening 274. Circular passage 273
A hydrogen peroxide absorbent 275 is disposed therein near the outer opening 272, and the hydrogen peroxide absorbent 275 prevents hydrogen peroxide from passing through the annular passage 273. The test pack 270 further has a chemical indicator 276, which typically has a strip with a chemical that changes color when exposed to hydrogen peroxide. A chemical indicator 276 is located within the annular passage 273 near the inner opening 274 and provides a visual indication that the test pack 270 has been exposed to hydrogen peroxide. Such a test pack 270 is available from Ir.
Available from Advanced Sterilization Products, Inc. of vine (ref. 14310).

The purpose of test pack 270 is to prevent hydrogen peroxide from accessing (reaching) biological indicator 271 to simulate (simulate) the diffusion-restricted region of load 260. . Inner opening 27
4, the dimensions of the various components of the test pack 270, such as the outer opening 272, the elliptical annular passage 273, the hydrogen peroxide absorbent 275, and the hydrogen peroxide to the diffusion limited region of the load 260. It may be designed to simulate diffusion. This design of test pack 270 typically combines a series of multiple biomarkers 271 in various test packs 270 of different sizes with a biomarker in the diffusion-constrained region of load 260. Requires a large number of sterilization tests (sterilization trials) to make comparisons. Test pack 2
If the biomarker readings in 70 and the biomarker readings in load 260 match, the test pack 270 provides a simulation of the diffusion-constrained region of load 260.

Further, when multiple items to be sterilized are placed in sterilization system 210 as load 260,
Typically, some articles are less accessible to hydrogen peroxide directly than others. To test the performance of the sterilization system 210 on articles where hydrogen peroxide vapor is the least accessible, test pack 270 is placed at a location where the concentration of hydrogen peroxide may be significantly reduced.
To place. In this way, the test pack 270 simulates a portion of the load 260 where sterilization is most difficult. Once it is ascertained that the biological indicators 271 of the test pack 270 have been sterilized, the entire load 260 is also considered sterilized.

However, the biological indicator 271 of test pack 270 provides information about the sterilization process only after the sterilization period has expired. Even more problematic, the results from test pack 270 are typically only obtained after the culture period has elapsed. In addition, test pack 270 cannot be reused because the package of test pack 270 is torn to access and retrieve the biological indicator.

FIG. 15 is a flow diagram showing the steps of a method 300 according to an embodiment of the invention. During the sterilization process, the method 300 of the present invention enables monitoring of the concentration of oxidizing gas (or oxidizing vapor) within the diffusion-restricted region 400 in fluid communication with the sterilization chamber 220 during the sterilization process. . The flow diagram of FIG. 15 is described with reference to FIG. 16 which schematically illustrates a diffusion constrained region 400 and a concentration monitor 410 compatible with embodiments of the present invention. Although the flow diagram of FIG. 15 illustrates a particular embodiment with a particular order of steps, those skilled in the art will understand that other embodiments with different order of steps are also compatible with the present invention.

In operation block (step) 310, a concentration monitor 410 is provided. Concentration monitor 410 produces variables in response to oxidizing gas (or oxidizing vapor). In one embodiment, as illustrated schematically in FIG. 16, the concentration monitor 410 includes a first temperature sensing device 412 and a chemical that reacts with an oxidizing gas (or oxidizing vapor) to generate heat. 414 and. The first temperature detection device 412 is coupled to the chemical substance 414 and generates a first signal in response to heat generated by the reaction between the chemical substance 414 and the oxidizing gas (or oxidizing vapor). The variable is generated in response to the first signal. As illustrated schematically in FIG. 16, the first temperature sensing device 412 of an embodiment comprises a first thermocouple junction and the first signal comprises a first voltage.

In another embodiment, the concentration monitor 410
Further includes a second temperature sensing device 416 that produces a second signal, the variable being produced in response to the second signal as well. In such other embodiments, the second temperature sensing device 416 comprises a second thermocouple junction that produces a second voltage. In yet another embodiment, the second thermocouple junction 416 is connected in series with the first thermocouple junction 412. Exposing the chemical substance 414 to an oxidizing gas (or oxidizing vapor) responds to the first voltage and the second voltage across the entire first thermocouple junction 412 and the second thermocouple junction 416. A voltage is produced, the overall voltage of which corresponds to the concentration of oxidizing gas (or oxidizing vapor).

In one embodiment, the concentration monitor 410
Further includes an electrical connector 418 that facilitates connecting and disconnecting the concentration monitor 410 and a chemical concentration monitoring system (not shown). In other embodiments,
A concentration monitor 410 with a separate reference temperature probe may be used. In yet another embodiment, the concentration monitor 410 may be used without the reference temperature probe. Other types of concentration monitors that provide a variable corresponding to the concentration of the oxidizing gas (or oxidizing vapor) and are located at least partially within the diffusion-constrained region are also compatible with embodiments of the present invention. It is understood by the trader.

In the operation block (step) 320, at least a part of the concentration monitor 410 is arranged in the diffusion-restricted region 400. As schematically shown in FIG. 16, the portion of the concentration monitor 410 located within the diffusion restricted region 400 has a chemical 414. In one embodiment, the diffusion constrained region 400 includes an outer passage 431, an elliptical annular passage 432, an inner passage 433, as schematically shown in FIG.
And test pack 430 including hydrogen peroxide absorbent 434
Form part of. The test pack 430 is placed in a sterilization system 440 in which a load 260 is placed, as shown schematically in FIG. However, instead of a prior art test pack that uses biological indicators, a test pack 430 compatible with embodiments of the present invention has a concentration monitor 410.
To use. Further, as described more fully below, the concentration monitor 410 provides a real-time measurement of the concentration of oxidizing gas (or oxidizing vapor) during the sterilization process, so that the test pack 430 is conventional. Does not require test pack chemistry indicators.

In operation block (step) 330, oxidizing gas (or oxidizing vapor) is introduced into the sterilization chamber 220. Since the diffusion limited region 400 is in fluid communication with the sterilization chamber 220, the oxidizing gas (or oxidizing vapor) is also sought in the (with chemicals 412) portion of the concentration monitor 410 within the diffusion limited region 400. Reach at the concentration to be achieved.

In operational block (step) 340, the variables generated by concentration monitor 410 during the sterilization process are monitored. The variable represents the concentration of the oxidizing gas (or oxidizing vapor) in the diffusion restricted region 400. In this way, the concentration of oxidizing gas (or oxidizing vapor) within diffusion limited region 400 is monitored during the sterilization process.

As schematically illustrated in FIG. 16,
A concentration monitor 410 includes a first thermocouple junction 412 coupled with a chemical 414 and a first thermocouple junction 412.
In an embodiment having a second thermocouple junction 416 connected in series with the variable, the variable is the concentration in response to the overall voltage across the first thermocouple junction 412 and the second thermocouple junction 416. Generated by monitor 410. This overall voltage is a function of the temperature difference between the first thermocouple junction 412 and the second thermocouple junction 416. This temperature difference is the result of the reaction of the chemical substance 414 with the oxidizing gas (or oxidizing vapor), which reaction is detected by the first thermocouple junction 412 and not by the second thermocouple junction 416. Generates heat. The amount of heat generated by the chemical substance 414 corresponds to (correlates with) the concentration of the oxidizing gas (or oxidizing vapor).

In one embodiment, the operation block (step) 340 further includes the variable generated by the concentration monitor 410 being a measure of the concentration of the oxidizing gas (or oxidizing vapor) in the diffusion constrained region 400. Convert to. In the embodiment in which the concentration monitor 410 schematically illustrated in FIG. 16 is used, the first thermocouple junction 412 is used.
And a calibration table is typically required to convert variables based on measurements of overall voltage across the second thermocouple junction 416 to measurements of concentration. Such a calibration table is
Exposing the concentration monitor 410 to a known concentration of oxidizing gas (or oxidizing vapor) to the total voltage across the first thermocouple junction 412 and the second thermocouple junction 416 for each of the known concentrations. Created by recording the variable based. In this way, the diffusion constrained region 400
A real-time measurement of the concentration of oxidizing gas (or oxidizing vapor) within is provided.

FIG. 18 illustrates a method 500 for determining the suitability of a load 260 for oxidative gas (or oxidative vapor) sterilization during a sterilization process according to another embodiment of the present invention.
It is a flowchart which shows the process of. In operation block (step) 510, load 260 is placed in sterilization chamber 220, and in operation block (step) 520, at least a portion of concentration monitor 410 is sterilization chamber 22.
It is placed in a diffusion constrained region 400 in fluid communication with zero. The concentration monitor 410 responds to the oxidizing gas (or oxidizing vapor) and produces a variable corresponding to the concentration of the oxidizing gas (or oxidizing vapor). As mentioned above, FIG. 16 schematically illustrates a concentration monitor 410 and diffusion constrained region 400 compatible with this embodiment of the invention.

At operation block (step) 530, the sterilization chamber 220 is evacuated, and at operation block (step) 540, oxidizing gas (or oxidizing vapor) is introduced into the sterilization chamber 220. In this way, the load 2
60 is contacted with oxidizing gas (or oxidizing vapor). The diffusion restricted region 400 is in fluid communication with the sterilization chamber 220 so that the concentration monitor 410 is exposed to oxidizing gas (or oxidizing vapor).

In operation block (step) 550, the variables generated by the concentration monitor 410 are monitored. As mentioned above, the variable is a diffusion-constrained region 4
The concentration of the oxidizing gas (or oxidizing vapor) in 00 is shown. In the operation block (step) 560, the load 260
Is determined from a variable indicating the concentration of the oxidizing gas (or oxidizing vapor) in the diffusion restricted region 400.

Typically, the sterilization process is properly loaded 2.
If it is expected that 60 has been sterilized, its load 26
0 is recognized as suitable for use. In prior art systems, the suitability of load 260 is determined by testing biological indicator 271 in test pack 270, which simulates a diffusion-constrained area in load 260. If the biological indicator 271 retrieves less than a predetermined number of viable microorganisms after being exposed to the sterilization process, then the load 260 is deemed suitable for use. As mentioned above, this prior art procedure
Allow the adequacy of the load 260 to be determined only after the incubation period, which takes several days after performing the sterilization process, is complete.

On the contrary, by using the concentration monitor 410 according to the embodiment of the present invention, the adequacy of the load 260 can be determined during the sterilization process, and the problematic time delay can be avoided. . By recording the results from the biological indicators in the diffusion constrained region 400 as a function of the concentration of oxidizing gas (or oxidizing vapor) measured by a concentration monitor 410 in the diffusion constrained region 400. , Correlation between concentration variables and sterilization process results is required. Once this correlation is determined, the concentration readings from concentration monitor 410 are used to determine the results of subsequent sterilization processes and subsequent loads 260.
Can be determined. The load (sterilized article) 260 is then released for use as soon as the variables during the sterilization process are found to be within acceptable limits. In this way, releasing the load (article) based on a variable such as the reading of the concentration from the concentration monitor 410 is called a variable release (parametric release) of the load 260. Systems that use variable release of articles, rather than systems that use biological indicators, benefit from shorter turnaround times, reduced costs, less handling of articles, and therefore reduced potential for post-sterilization contamination. provide.

Embodiments of the present invention can define thresholds of exposure to oxidizing gas (or oxidizing vapor) for a successful sterilization process in various ways. In one embodiment, a successful process (ie, a sterilization process that produces an appropriate load) is defined as one that achieves a minimum concentration level of oxidizing gas (oxidizing vapor). In such an embodiment, if the concentration monitor 410 indicates that the diffusion-restricted region was exposed to at least this minimum concentration level (of oxidizing gas (or oxidizing vapor)) during the sterilization process: The load is deemed appropriate and is released. Instead, in another embodiment, if the measured concentration of oxidizing gas (or oxidizing vapor) during the sterilization process measured by the concentration monitor 410 changes, then the rate of change (rate) is used to sterilize. The success of the process is determined. In some such embodiments, the diffusion constrained region is exposed to (a oxidizing gas (or oxidizing vapor) of) a concentration measurement of decreasing rate (decreasing rate) not exceeding a maximum value. The load is deemed appropriate and is released. In another of such embodiments, the diffusion constrained area is exposed to (a oxidizing gas (or oxidizing vapor) of) a concentration measurement of increasing rate of change (increasing rate) not below a minimum value. If so, the load is deemed appropriate and is released. In yet another embodiment,
A time-integrated concentration measurement (ie, the area between the concentration measurement curve and the time axis during the sterilization process) within the diffusion-constrained region is used to determine the diffusion-constrained region. The load is deemed appropriate and is released when the is exposed to a minimum concentration value that has been integrated for at least time. Other embodiments of the present invention may use other definitions of the success of the sterilization process as determined by the concentration of oxidizing gas (or oxidizing vapor) within the diffusion limited region determined by concentration monitor 410. .

If the load is determined to be adequate, the sterilization process is allowed to continue. If it is determined that the load is not adequate, then in one embodiment the sterilization process is stopped. Alternatively, when it is determined that the load is not adequate, in another embodiment, additional oxidizing gas (or oxidizing vapor) is introduced into the sterilization chamber 220. In yet another embodiment, if the load is determined to be improper, the condition is communicated to the user as an alert. Such embodiments may include a control feedback mechanism for controlling the process variable.

The use of the concentration monitor 410 in the diffusion-constrained area 400, such as the test pack 430, offers several additional advantages over prior art methods that use biological indicators. First, the concentration monitor 410 provides an oxidizing gas (or oxidizing vapor) within the diffusion-limited region 400 at various times during the sterilization process.
The concentration of can be monitored. By controlling the vacuum system and a source of oxidizing gas (or oxidizing vapor) in response to concentration measurements in diffusion-constrained region 400 during the sterilization process, sterilization system 440 can be used throughout the sterilization process. The concentration level of can potentially be maintained dynamically. Second, cost can be reduced because the concentration monitor 410 can be used repeatedly for multiple sterilization processes compared to biological indicators that can only be used once.

In one embodiment, the concentration monitor 410
Are conveniently placed in other diffusion-constrained regions of test pack 430 other than diffusion-constrained region 400. As shown schematically in FIG. 19, in one embodiment, the diffusion restricted region comprises a region 500 inside the lumen 510. The lumen 510 of an embodiment is
T-type connector 51 for accommodating a part of the concentration monitor 410
6 has a first tube 512 and a second tube 514 coupled to it. The first tube 512, the second tube 514, and the T-connector 516 are joined together by a pair of latex tube connectors 518 to form a lumen 510. The concentration monitor 410 is coupled to the T-shaped connector 516 via a non-conductive epoxy 520, which is a T-type connector through which the concentration monitor 410 penetrates.
The mold connector 516 is sealed. First tube 51
2, the second tube 514, and the T-connector 516 are in fluid communication with each other and with the atmosphere within the sterilization chamber 220. In one embodiment, the first tube 51
The dimensions of 2, the second tube 514, and the T-connector 516 are designed to mimic the dimensions of the lumen within the load 260 to be sterilized.

As shown schematically in FIG. 20, in one embodiment, lumen 510 is located inside a container 530 in fluid communication with sterilization chamber 220.
In some embodiments, container 530 has one or more openings 540 that are uncovered, and in other embodiments container 530 is made of gas permeable material. One example of such an embodiment has a lumen 510 located in a sterile tray covered with CSR wrap.

As shown schematically in FIG. 21, in one embodiment, the diffusion constrained region is a process region.
It consists of an inner region 600 within a challenge device (PCD) 610. In one embodiment, the PCD 610 includes an outer cylinder 612 and an inner cylinder 61 slidably coupled to the outer cylinder 612 to define an inner region 600.
4 and. Inner cylinder 614 has at least one opening 616. In the embodiment schematically shown in FIG. 21, the inner cylinder 614 has a plurality of openings 61.
Do 6. The inner cylinder 614 has a plurality of openings 616.
Of the plurality of openings 616 can be arranged such that a second portion (remaining portion) of the plurality of openings 616 provides a fluid connection between the inner region 600 of the PCD and the sterilization chamber 220. The inner cylinder 614 can be slid into various positions to change the proportion of the openings 616 closed by the outer cylinder 612, and thus the inner region 600 and sterilization chamber 22.
The diffusion path between 0 and 0 can be changed. In this way, the PCD 610 is loaded 26 like a packaged device.
It can be adjusted to simulate a diffusion constrained region in zero.

As shown schematically in FIG. 22, in one embodiment, the diffusion-restricted region comprises a region 700 within the second chamber 710 in fluid communication with the sterilization chamber 220. Conduit 720 provides a fluid connection between sterilization chamber 220 and second chamber 710. In certain embodiments, the dimensions of conduit 720 are designed such that diffusion of oxidizing gas (or oxidizing vapor) into region 700 mimics diffusion into a diffusion-constrained region within load 260. Instead, the dimensions of the conduit 720 are designed to have no appreciable effect on the diffusion of the oxidizing gas (or oxidizing vapor) and the concentration monitor 41
0 is a P that simulates a diffusion constrained region in load 260
It may be placed in the CD 610 or the test pack 430.

The concentration monitor 410 of one embodiment is
Chemical concentration measuring system 730 of concentration monitor 410
A connector 418 that facilitates electrical connection and disconnection to and from. The embodiment with the second chamber 710 facilitates access to the concentration monitor 410.

As shown schematically in FIG. 23, in one embodiment, the diffusion constrained region is a load 260.
It consists of an area 800 inside. In some such embodiments, the area 800 is located inside a package 810 containing the device 820 to be sterilized.
Each package 810 has a gas permeable portion 812 so that the device 820 can be packaged and then sterilized so that the packaged and sterilized device 820 can be shipped to a customer. As shown schematically in FIG. 23, the package 810 includes a concentration monitor 410 that measures the concentration of oxidizing gas (or oxidizing vapor) within the area 800 occupied by the device 820 to be sterilized. Good. In embodiments using the concentration monitor 410 with a thermocouple conductive film, the conductive film may be incorporated as part of the package 810. By using the concentration monitor 410 with the device 820 to be sterilized, the device 82 to the oxidizing gas (or oxidizing vapor) during sterilization of the load 260.
Information about the exposure of 0 is obtained and can be used to provide a specific rating for each device 820 of the sterilization process.

So far, various embodiments of the present invention have been described. Although the invention has been described with reference to these specific embodiments, the descriptions are intended to be illustrative of the invention and not limiting. Various modifications and alterations will occur to those skilled in the art without departing from the spirit and scope of the invention as defined by the claims.

Specific embodiments of the present invention are as follows. (1) The oxidizing gas or oxidizing gas of claim 1, wherein the concentration monitor further comprises a second temperature sensing device that produces a second signal, the variable being produced in response to the second signal as well. How to monitor the concentration of steam. (2) The method for monitoring the concentration of oxidizing gas or oxidizing vapor according to claim 1, wherein the first temperature detecting device comprises a first thermocouple junction, and the first signal comprises a first voltage. (3) The oxidation of embodiment (2), wherein the concentration monitor further comprises a second thermocouple junction that produces a second voltage, and the variable is also produced in response to the second voltage. A method of monitoring the concentration of gas or oxidizing vapor. (4) The second thermocouple junction is connected in series with the first thermocouple junction, and the variable is responsive to the first voltage and the second voltage. The method of monitoring the concentration of oxidizing gas or oxidizing vapor according to embodiment (3), which is also produced in response to the overall voltage produced across the second junction. (5) The step of monitoring the concentration further comprises the step of converting the variable generated by the concentration monitor into a measurement of the concentration of the oxidizing gas or oxidizing vapor in the diffusion restricted region. A method for monitoring the concentration of oxidizing gas or oxidizing vapor.

(6) The method for monitoring the concentration of an oxidizing gas or an oxidizing vapor according to claim 1, wherein the oxidizing gas or the oxidizing vapor comprises hydrogen peroxide. (7) The method for monitoring the concentration of oxidizing gas or oxidizing vapor according to claim 1, wherein the diffusion-restricted region comprises a region inside the test pack. (8) The method for monitoring the concentration of oxidizing gas or vapor according to claim 1, wherein the diffusion-restricted region comprises a region inside the lumen. (9) The method of monitoring the concentration of oxidizing gas or vapor according to embodiment (8), wherein the lumen comprises an area inside the container in fluid communication with the sterilization chamber. (10) The method for monitoring the concentration of oxidizing gas or oxidizing vapor according to claim 1, wherein the diffusion-restricted region comprises a region inside the process challenge device.

(11) the process challenger is adjustable to alter the diffusion passage between the area inside the process challenger and the sterilization chamber,
The method of monitoring the concentration of oxidizing gas or vapor according to embodiment (10), further comprising the step of adjusting the process challenge device to simulate a second diffusion constrained region in the load. (12) The method for monitoring the concentration of oxidizing gas or oxidizing vapor according to claim 1, wherein the diffusion-restricted region comprises a region inside a second chamber in fluid communication with the sterilization chamber. 13. The oxidizing gas or oxidation of claim 1, wherein the diffusion constrained region is designed to simulate the diffusion of oxidizing gas or vapor into a second diffusion constrained region of the load. How to monitor the concentration of steam. (14) The method for monitoring the concentration of oxidizing gas or oxidizing vapor according to claim 1, wherein the diffusion-restricted area comprises an area inside the packaged device. (15) The method for monitoring the concentration of oxidizing gas or oxidizing vapor according to claim 1, further comprising the step of placing a load in the sterilization chamber and determining the suitability of the load.

(16) Embodiments in which the concentration monitor further comprises a control feedback mechanism for controlling the process variables of the sterilization system, and further comprises the step of controlling the process variables in response to the judgment of the adequacy of the load. 15) A method for monitoring the concentration of oxidizing gas or oxidizing vapor according to 15). (17) The embodiment (1) further comprising the step of stopping the sterilization process in response to the determination that the load is not appropriate.
5) A method for monitoring the concentration of the oxidizing gas or oxidizing vapor according to 5). (18) The embodiment (15), further comprising a step of further introducing an oxidizing gas or an oxidizing vapor into the sterilization chamber in response to the determination that the load is not appropriate. (19) The method for monitoring the concentration of oxidizing gas or oxidizing vapor according to the embodiment (15), further comprising the step of generating an alarm in response to the determination that the load is not appropriate. (20) The embodiment (15), wherein the step of determining the appropriateness of the load includes the step of defining a minimum concentration level of the oxidizing gas or oxidizing vapor in the diffusion-constrained region corresponding to the appropriate load. Method for monitoring the concentration of oxidizing gas or oxidizing vapor in.

(21) The process of determining the appropriateness of the load is
Monitoring the oxidizing gas or oxidizing vapor concentration according to embodiment (15), comprising the step of defining a maximum rate of decrease of the oxidizing gas or oxidizing vapor concentration in the diffusion constrained region corresponding to an appropriate load. Method. (22) The step of determining the appropriateness of the load includes the step of defining a minimum increase rate of the concentration of the oxidizing gas or the oxidizing vapor in the diffusion-constrained region corresponding to the appropriate load,
A method for monitoring the concentration of oxidizing gas or oxidizing vapor according to embodiment (15). (23) The embodiment in which the step of determining the adequacy of the load includes the step of defining a minimum time integral value of the concentration of the oxidizing gas or the oxidizing vapor in the diffusion-constrained region corresponding to the appropriate load ( 15) A method for monitoring the concentration of oxidizing gas or oxidizing vapor according to 15) (24) The device for monitoring the concentration of oxidizing gas or oxidizing vapor according to claim 2, wherein the first temperature detecting device comprises a first thermocouple junction, and the first signal comprises a first voltage. (25) The oxidizing gas or oxidizing vapor of claim 2, wherein the concentration monitor further comprises a second temperature sensing device that produces a second signal, the variable being produced in response to the second signal. Device to monitor the concentration of.

(26) The concentration of the oxidizing gas or the oxidizing vapor according to the embodiment (25), wherein the second temperature detecting device comprises a second thermocouple junction, and the second signal comprises a second voltage. Device to monitor. (27) The second thermocouple junction is connected in series with the first thermocouple junction, and the variable is responsive to the first voltage and the second voltage. An apparatus for monitoring the concentration of oxidizing gas or vapor as described in embodiment (26), which is also produced in response to the overall voltage produced across the second junction.

[0088]

As described above, according to the present invention, there is an effect that a real-time (real-time) measurement value of the concentration of the oxidizing gas (or oxidizing vapor) in the diffusion restricted region is provided.

According to the present invention, it is possible to determine the appropriateness of the load during the sterilization process, and it is possible to avoid a problematic time delay.

According to the present invention, rather than a biological indicator,
The use of variable release of articles has the advantage of providing the benefits of shorter turnaround times, reduced costs, less handling of articles and therefore reduced potential for contamination after sterilization.

According to the present invention, the concentration of oxidizing gas (or oxidizing vapor) in the diffusion-limited region at various times during the sterilization process can be monitored, and the vacuum system and oxidizing gas (or oxidizing vapor) can be monitored. Controlling the source as a function of the concentration measurements in the diffusion-limited region during the sterilization process has the effect of potentially dynamically maintaining the desired concentration level throughout the sterilization process.

According to the present invention, the concentration monitor can be repeatedly used for a plurality of sterilization processes, as compared with the biological index which can be used only once, and thus there is an effect that the cost can be reduced.

In accordance with the present invention, the concentration monitor is used with the device to be sterilized to provide information about the exposure of the device to oxidizing gas (or oxidizing vapor) during sterilization of the load, and sterilizing that information. There is an effect that can be used to provide a device-specific assessment of the process.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an embodiment of a concentration monitor compatible with an embodiment of the present invention, which includes a carrier, a chemical substance, and a temperature probe.

FIG. 2 is a schematic diagram of an embodiment of a concentration monitor compatible with an embodiment of the present invention that includes a carrier, a chemical, and a temperature probe.

FIG. 3 is a schematic diagram of an embodiment of a concentration monitor compatible with an embodiment of the present invention, which includes a carrier, a chemical substance, and a temperature probe.

FIG. 4 is a schematic diagram of an embodiment of a concentration monitor compatible with an embodiment of the present invention that includes a carrier, a chemical, and a temperature probe.

FIG. 5 is a schematic diagram of an embodiment of a concentration monitor compatible with an embodiment of the present invention, including a carrier, a chemical, and a temperature probe.

FIG. 6 is a schematic diagram of a sterilization system compatible with an embodiment of the present invention.

FIG. 7 is a schematic diagram of an embodiment of a concentration monitor equipped with a reference temperature probe adapted to the embodiment of the present invention.

FIG. 8 is a schematic diagram of an embodiment of a concentration monitor equipped with a reference temperature probe adapted to an embodiment of the present invention.

FIG. 9 is a schematic diagram of an embodiment of a concentration monitor equipped with a reference temperature probe adapted to the embodiment of the present invention.

FIG. 10 is a schematic diagram of an embodiment of a concentration monitor including a reference temperature probe adapted to the embodiment of the present invention.

FIG. 11 is a schematic view of an embodiment of a concentration monitor including a reference temperature probe that is compatible with the embodiment of the present invention.

FIG. 12A is a schematic diagram of a concentration monitor including an integrated circuit chip adapted to the embodiment of the present invention.
(B) is a schematic view of a concentration monitor having a thermocouple junction made of a conductive thin film, which is suitable for the embodiment of the present invention.

FIG. 13 is a schematic diagram of a sterilization system disclosed in the related art.

FIG. 14 is a schematic diagram of a test pack disclosed in the related art.

FIG. 15 is a flow chart of a method for determining the concentration of oxidizing gas (or oxidizing vapor) in a diffusion constrained region according to an embodiment of the invention.

FIG. 16 is a schematic diagram of a diffusion limited region and concentration monitor compatible with the present invention.

FIG. 17 is a schematic diagram of a test pack placed in a sterilization system with a load according to an embodiment of the invention.

FIG. 18 is a flow chart of a method for determining adequacy of load for sterilization with oxidizing gas (or oxidizing vapor) according to another embodiment of the present invention.

FIG. 19 is a schematic view of a portion of a concentration monitor inside a lumen according to an embodiment of the present invention.

FIG. 20 is a schematic diagram of a portion of a concentration monitor inside a lumen disposed inside a container with an opening covered with a gas permeable material according to an embodiment of the present invention.

FIG. 21 is a schematic diagram of a portion of a concentration monitor in a process challenge device (PCD) according to an embodiment of the invention.

FIG. 22 is a schematic diagram of a portion of a concentration monitor in a second chamber fluidly connected to a sterilization chamber via a conduit.

FIG. 23 is a schematic view of a portion of a concentration monitor in a package having a gas permeable portion and accommodating an apparatus according to an embodiment of the invention.

[Explanation of symbols]

10 Concentration monitor 12 career 14 chemical substances 16 Temperature probe 17 Heat seal part 18 Thermally conductive material 19 board 20 male connector 21 female connector 25 Sterilization system 30 vacuum chamber 32 doors 34 Door Controller 40 gas inlet system 42 Hydrogen peroxide supply source 44 valves 46 valve controller 50 gas outlet system 52 Vacuum pump system 54 valves 56 valve controller 58 Vacuum pump system controller 60 radio frequency system 62 Ground electrode 64 Powered electrode 66 power 68 Power Controller 70 Control system 80 articles 90 Reference temperature probe 100 microprocessor 102 Data acquisition channel 104 data acquisition channel 110 First Thermocouple Junction 112 First conductor 114 Second conductor 116 Third conductor 120 Second thermocouple junction 130 First connector 132 Second connector 134 cable 136 data acquisition channels 138 microprocessor 140 integrated circuit chips 142 output pins 150 concentration monitor 152 output pins 210 Sterilization system 220 Sterilization chamber 230 Hydrogen peroxide supply source 240 concentration monitor 242 UV light source 244 UV Spectrometer 250 vacuum system 252 valve 254 pump 256 ventilation openings 260 load 270 test pack 271 biological indicators 272 Outer opening 273 ring passage 274 inner opening 275 Hydrogen peroxide absorbent 276 Chemical Index 400 diffusion constrained region 410 Concentration monitor 412 First temperature detection device 414 chemical substances 416 Second temperature detection device 418 connector 430 test pack 431 outer passage 432 circular passage 433 inner passage 434 Hydrogen peroxide absorbent 440 Sterilization system 500 areas 510 lumen 512 first tube 514 Second tube 516 T type connector 518 Tube Connector 520 epoxy 530 container 540 opening 600 inner area 610 Process Challenge Device 612 outer cylinder 614 Inner cylinder 616 opening 700 areas 710 Second chamber 720 conduit 730 Concentration measurement system 800 areas 810 package 812 Gas permeable part 820 device

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tin-Min Lin             United States, 92653 California             State, Laguna Hills, Rain Tree             Road 25632 (72) Inventor Debra Tim             United States, 92610 California             State, Foothill Ranch, Alta Vista               18 (72) Inventor Anthony Remus             United States, 92861 California             State, Villa Park, Eggplant Circle             10161 (72) Inventor Ben Flyer             United States, 92630 California             State, Lake Forest, View Point             To 25691 (72) Inventor Keith Engstrom             United States, 92677 California             Province, Laguna Niguel, Argos 8 F-term (reference) 2G040 AA03 AB15 BA23 CA03 CB07                       DA02 DA05

Claims (2)

[Claims] 1. A method for monitoring the concentration of oxidizing gas or vapor in a diffusion-confined region in fluid communication with a sterilization chamber during a sterilization process, the variable being responsive to the oxidizing gas or vapor. Wherein the concentration monitor comprises a first temperature detecting device and a chemical substance that reacts with the oxidizing gas or the oxidizing vapor, wherein the first temperature detecting device comprises: Coupled to the chemical and producing a first signal in response to heat generated by the chemical and the oxidizing gas or vapor, the variable in response to the first signal. Producing a concentration monitor, arranging at least the chemical bound portion of the concentration monitor in the diffusion limited region, and placing the concentration monitor in the sterilization chamber. Monitoring the variable generated by the concentration monitor during the sterilization process and the step of introducing oxidizing gas or vapor to ensure that the oxidizing gas or the oxidizing gas in the diffusion-restricted region during the sterilization process Monitoring the concentration of oxidizing vapor, and a method of monitoring the concentration of oxidizing gas or oxidizing vapor. 2. An apparatus for monitoring the concentration of oxidizing gas or oxidizing vapor in a sterilization chamber during a sterilization process, the diffusion-confined region in fluid communication with the sterilizing chamber, and the oxidizing gas or oxidizing vapor. Generate a variable in response to
A concentration monitor at least partially disposed in the diffusion-restricted region, the concentration monitor comprising:
And a chemical substance that reacts with the oxidizing gas or oxidizing vapor. The first temperature detecting device is coupled to the chemical substance, and the chemical substance and the oxidizing gas or oxidizing vapor are included. Monitor a concentration of an oxidizing gas or vapor that produces a first signal in response to heat generated by and the variable is produced in response to the first signal. Device to do.